Microstructure and properties of a nano-ZrO2-reinforced AlSi10Mg matrix composite prepared by selective laser melting

In this study, nano-ZrO2-reinforced AlSi10Mg composites were prepared using a high-speed homogenizer and samples were fabricated by selective laser melting (SLM) technique. The effects of ZrO2 on the microstructures, crystallographic textures and mechanical properties of the ZrO2/AlSi10Mg composites were studied. The results show that ZrO2 particles were distributed uniformly and had good interfacial bonding with the AlSi10Mg matrix. The incorporation of ZrO2 reduced the formation of large crystalline grains and had an important role in grain refinement. The small-angle grain boundaries and (001) crystal orientation were greatly enhanced. Compared with AlSi10Mg, ZrO2/AlSi10Mg had superior mechanical properties, including the highest hardness strength of 139 HV (an average increase of 10.3%), a tensile strength of 478.6 MPa and an elongation of 10.6% (increases of 13.5% and 41%, respectively).